Boutonnière Deformity

Upper Limb

Overview

Boutonnière deformity is a finger deformity characterized by flexion of the proximal interphalangeal (PIP) joint and extension of the distal interphalangeal (DIP) joint, resulting from disruption of the extensor mechanism at the PIP level. This condition commonly develops following trauma to the dorsal aspect of the PIP joint, rheumatoid arthritis, or other inflammatory conditions affecting the extensor apparatus. Early recognition and appropriate management are critical to prevent fixed contracture and functional loss.

Pathophysiology

Boutonnière deformity develops when the central slip of the extensor tendon is damaged or attenuated, disrupting the primary extension force at the PIP joint. As the central slip weakens, the lateral bands migrate volarly (toward the palm) relative to the joint axis, converting them from extensors to flexors of the PIP joint. Simultaneously, these volar lateral bands become more efficient extensors of the DIP joint, creating the characteristic posture: PIP flexion with compensatory DIP hyperextension. Chronic inflammation in rheumatoid arthritis can similarly erode the central slip insertion. Without intervention, the deformity becomes fixed as secondary contractures develop in the volar capsule and flexor tendon sheath, making restoration of full extension increasingly difficult.

Patient Education

Early gentle active-assisted range of motion exercises and proper splinting are essential to prevent permanent deformity; avoid aggressive passive stretching which may worsen inflammation or cause iatrogenic injury.

Typical Presentation

Site

Proximal interphalangeal (PIP) joint of affected finger(s), typically index through little finger; dorsal surface at joint level

Quality

Aching, stiffness, reduced active extension; variable pain depending on causative trauma or inflammatory activity

Intensity

Mild to moderate ache; severity increases with attempted active extension or functional use

Aggravating

Active extension of PIP joint, gripping activities, flexion/extension cycling movements, inflammatory flare-ups in rheumatoid arthritis

Relieving

Rest, anti-inflammatory modalities, splinting in extension, gentle passive flexion within pain-free range

Associated

Swelling over dorsal PIP joint, loss of active PIP extension (may retain passive extension early), progressive loss of functional grasp, visible finger deformity, sensory changes if nerve involvement, warmth and erythema if inflammatory

Orthopaedic Tests

Test descriptions are written with AI assistance from standard clinical texts. Where a test lists Sources, its description has been checked against them; those sources are independent and do not endorse OsteoKit. Accuracy figures and grades (A–D) appear only when checked against the published study; tests without one are marked “No accuracy study”.

Further reading: full test procedures are described in standard clinical examination texts, e.g. Magee & Manske, Orthopedic Physical Assessment (7th ed.), and Cook & Hegedus, Orthopedic Physical Examination Tests: An Evidence-Based Approach (2nd ed.).

No accuracy study

Boutonnière Test (DIP Flexion Lag)

Procedure

Hold the PIP joint in full extension and ask the patient to bend the DIP joint, then try it passively. Repeat with the PIP joint bent. (This is the Haines–Zancolli test.)

Positive Finding

The DIP joint cannot be bent, actively or passively, while the PIP is held straight, but bends once the PIP is flexed.

Interpretation

Shows tightness of the oblique retinacular ligament and lateral bands, a feature of established boutonnière deformity. It helps judge how long-standing and fixed the deformity is.

Sources

  • RelatedTubiana et al., 1998, The Hand — foundational hand examination text

Further reading

No accuracy study

PIP Joint Flexion Contracture Assessment

Procedure

Passively extend the PIP joint and measure any remaining flexion with a finger goniometer.

Positive Finding

The PIP joint cannot be passively straightened fully.

Interpretation

A PIP that still straightens passively means a flexible deformity, usually treated with splinting. A fixed flexion contracture means a longstanding deformity that may need serial splinting or surgery.

Sources

No accuracy study

Intrinsic Plus Test (Lumbricals and Interossei Function)

Procedure

Ask the patient to bend the MCP joints while keeping the finger joints straight.

Positive Finding

The PIP joint of the affected finger cannot be held straight.

Interpretation

Not a standard test for boutonnière deformity; it shows the same loss of active PIP extension seen at rest. The Elson test is the key test for a central slip injury.

Sources

  • RelatedNeumann, 2010, Kinesiology of the Musculoskeletal System — functional assessment standard

Further reading

No accuracy study

Central Slip Integrity Test (Modified Elson Test)

Procedure

Bend the patient's PIP joint to 90° over the edge of a table. Ask them to extend the middle phalanx against your resistance while you watch and feel the DIP joint.

Positive Finding

Weak or absent PIP extension with the DIP joint going rigid and extending. With an intact central slip the DIP stays floppy.

Interpretation

The most useful early test for an acute central slip injury, which can look normal in the first days before the boutonnière posture appears. A positive test needs the PIP splinted in extension and hand therapy or hand surgery referral.

Sources

No accuracy study

DIP Hyperextension Assessment

Procedure

Look at the DIP joint at rest and while the patient tries to straighten the finger, and test whether it can be bent passively.

Positive Finding

The DIP joint rests in hyperextension and resists bending, with the PIP flexed — the full boutonnière posture.

Interpretation

DIP hyperextension develops as the lateral bands slip towards the palm and tighten. A stiff hyperextended DIP means an established deformity that is harder to correct.

Sources

⚠ Red Flags

  • •Acute severe trauma with open wound or obvious tendon exposure—requires immediate surgical evaluation
  • •Signs of infection (increased warmth, purulent drainage, systemic fever)—indicates potential septic arthritis requiring urgent referral
  • •Complete inability to extend PIP joint acutely following trauma—suggests complete central slip rupture requiring urgent orthopedic assessment
  • •Progressive neurological symptoms (numbness, tingling, weakness)—suggests nerve compression or systemic rheumatologic disease
  • •Severe systemic inflammatory markers or polyarticular involvement—suggests systemic rheumatoid arthritis requiring rheumatologic referral
  • •Vascular compromise signs (pallor, coldness, delayed capillary refill)—indicates vascular injury requiring urgent vascular surgery

⚡ Yellow Flags

  • •Multiple finger involvement with morning stiffness >1 hour—suggests early inflammatory arthropathy with psychological impact of potential hand dysfunction
  • •Catastrophic thinking about permanent disability or loss of hand function—requires reassurance about prognosis with early intervention
  • •Poor compliance with splinting or exercise regimen—indicates need for motivational interviewing and realistic goal-setting
  • •Recent major trauma with psychological distress or anxiety about injury—may benefit from concurrent counseling or graded exposure approach
  • •Occupational or recreational activity requiring fine motor precision at risk—may require modified activity planning and psychosocial support

Osteopathic Techniques

A closed central slip injury seen within 4 weeks is usually treated with a splint that holds the PIP joint straight, full-time for 6–8 weeks and then at night for 4–6 weeks more, while the DIP keeps moving. Surgery is for late presentation, lacerations, displaced avulsion fractures or rheumatoid arthritis. No trials of osteopathic techniques were found.

Safety: The PIP must not bend while it is splinted, or the healing central slip can pull apart. Keep techniques off the PIP; the DIP should be moved actively and passively every day.

Region

Dorsal and volar forearm muscles (finger and wrist extensors and flexors)

Technique

Soft tissue, elbow and forearmNo trials found

Rationale

Soft tissue to the forearm flexor and extensor muscles that move the wrist and fingers.

How it's done, cautions & evidence

How it's done

Hands-on kneading, stroking and sustained pressure to the forearm extensor and flexor muscles, their tendon origins at the epicondyles, the supinator, the pronators and the triceps. Deep transverse friction across the tendon origin is part of the Cyriax method for lateral elbow pain.

Cautions

Avoid direct pressure on an olecranon bursitis. A red, warm, tender bursa, especially with fever, may be septic and needs medical review.

Evidence in Boutonnière Deformity

Searched 26 Oct 2026: no trials of forearm soft tissue in boutonnière deformity.

Rehabilitation Exercises

Gentle Active PIP Extension in Safe Position

Range of MotionBeginner

Controlled Finger Flexion and Extension (Full Fist to Hook Fist)

Range of MotionBeginner

Passive DIP Joint Flexion Stretch (Gentle Overpressure)

StretchingBeginner

Volar Forearm Flexor Stretching (Wrist and Finger Extension)

StretchingBeginner

Intrinsic Hand Muscle Activation (Lumbrical Exercises)

StrengtheningIntermediate

Extensor Digitorum Strengthening (Resistance Band or Light Weight)

StrengtheningIntermediate

Grip and Pinch Strengthening Progressions

StrengtheningIntermediate

Hand Positioning and Splinting Compliance (Dorsal Blocking Splint Education)

PosturalBeginner

Wrist and Upper Limb Postural Awareness Exercises

PosturalBeginner

Isolated MCP Flexion with PIP/DIP Extension (Intrinsic Plus Position)

Range of MotionIntermediate

Fine Motor Task Training (Picking Small Objects, Writing)

FunctionalIntermediate

Proprioceptive Retraining (Sensory Awareness and Finger Positioning)

BalanceIntermediate

Referral Criteria

  • •Acute traumatic injury with visible tendon rupture or open wound—immediate referral to hand surgeon for emergency evaluation and possible primary repair
  • •Complete loss of active PIP extension acutely following trauma—urgent orthopedic or hand surgery referral for assessment of central slip integrity and operative candidacy
  • •Progressive fixed flexion contracture unresponsive to 3-4 weeks of conservative management—referral to hand surgeon for consideration of surgical reconstruction (central slip repair or reconstruction)
  • •Signs of infection, increased swelling, warmth, or erythema—referral to physician or emergency department for assessment of cellulitis or septic arthritis
  • •Concurrent neurological symptoms (numbness, paresthesias, weakness beyond motor loss from PIP dysfunction)—referral to neurologist or hand surgeon for assessment of nerve compression or injury
  • •Polyarticular hand involvement with systemic symptoms (fever, rash, malaise) or prolonged morning stiffness—referral to rheumatologist for assessment of inflammatory arthropathy
  • •Poor functional recovery or chronic pain >6-8 weeks despite appropriate conservative care—referral to hand therapist specialist or hand surgeon for advanced rehabilitation or surgical options
  • •Vascular compromise signs (pallor, coldness, reduced sensation suggesting ischemia)—immediate referral to vascular surgeon or emergency department for vascular assessment